media: staging: rkisp1: params: don't release lock in isr before buffer is done

In the irq handler 'rkisp1_params_isr', the lock 'config_lock'
should be held as long as the current buffer is used. Otherwise the
stop_streaming calback might remove it from the list and
pass it to userspace while it is referenced in the irq handler.

Signed-off-by: Dafna Hirschfeld <[e-mail]>
Acked-by: Helen Koike <[e-mail]>
Signed-off-by: Hans Verkuil <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/staging/media/rkisp1/rkisp1-params.c

···
 	if (!list_empty(&params->params))
 		cur_buf = list_first_entry(&params->params,
 					   struct rkisp1_buffer, queue);
-	spin_unlock(&params->config_lock);
 
-	if (!cur_buf)
+	if (!cur_buf) {
+		spin_unlock(&params->config_lock);
 		return;
+	}
 
 	new_params = (struct rkisp1_params_cfg *)(cur_buf->vaddr);
 
···
 	/* update shadow register immediately */
 	rkisp1_param_set_bits(params, RKISP1_CIF_ISP_CTRL, RKISP1_CIF_ISP_CTRL_ISP_CFG_UPD);
 
-	spin_lock(&params->config_lock);
 	list_del(&cur_buf->queue);
-	spin_unlock(&params->config_lock);
 
 	cur_buf->vb.sequence = frame_sequence;
 	vb2_buffer_done(&cur_buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
+	spin_unlock(&params->config_lock);
 }
 
 static const struct rkisp1_cif_isp_awb_meas_config rkisp1_awb_params_default_config = {